1. Technical Field
Aspects of this document relate to public use key cutting and key duplication machines for reproducing keys. More specific implementations relate to simplified key duplication systems for identifying a predetermined number of keys for duplication.
2. Background Art
Conventionally, key cutting and key duplication machines are used to copy a key by cutting a bit pattern of a master key onto a key blank. It is known to use methods such as tracer bars, stylus, or other types of mechanical arms to trace a master key bit pattern. A trained operator conventionally was required to eyeball both a master key and a key blank and verify whether both keys are the same size and whether they comprise identical groves before attempting to cut the key. Once the key groves and key shape are verified, the master key and the key blank are placed in a key cutting machine such that the master key faces a stylus or a tracer bar and the key blank faces a cutting wheel.
After the keys are securely gripped by the key cutting machine, a carriage is manually shifted longitudinally along supporting shaft to trace the master key bit pattern so that the cutting wheel cuts the identical key pattern into the corresponding key blank. The key blank cut with the master key pattern is then removed from the grip and buffed on a buffing wheel to remove burrs.
An example of an elaborate system used to assist a trained worker in selecting an appropriate key blank and appropriately positioning the key blank and master key for cutting is disclosed in U.S. Pat. No. 5,443,339 to Heredia et al., titled “Method and Apparatus for Aligning and Cutting Single-sided and Double Sided Keys.” More recent master key identification systems, such as that disclosed in U.S. Pat. No. 6,836,553 to Campbell et al., titled “Key Identification System,” the disclosure of which is hereby incorporated herein by reference, automatically identifies the appropriate key blank and indicates that number for key selection.
A recent key duplication system described in International Application Number PCT/US2007/024522 to Freeman, et al. titled “Fully Automatic Key Duplicating Machine with Automatic Key Model Identification System” sought to reduce the need for the operation skills of a trained worker by automatically identifying master keys and automatically cutting and dispensing a duplicate key from a limited selection of keys within the key duplication system. Another recent key duplication system described in U.S. Pat. No. 7,890,878 to Bass et al., titled “Object Identification System,” discloses a system that identifies an appropriate key blank by flashing a light adjacent the appropriate key blank on a product display next to a key blank cutter so that the consumer or a trained worker can select the appropriate key for insertion into the key blank cutter.
More than sixty percent of keys duplicated in United States are made either by SCHLAGE and KWIKSET manufacturers. Complex cutting machines not only aggravate issues pertinent to key cutting among consumers, such as key miscuts, they also tend to confuse a consumer with their intricacies and the skill required to operate.